RNA is produced in the nucleolus of the cell and trav-
els to the cytoplasm through the pores of the nuclear
envelope.
nucleosides Compounds in which a purine or pyrim-
idine base is ß-N-glycosidically bound to C-1 of either
2-deoxy-D-ribose or of D-ribose, but without any
phosphate groups. The common nucleosides in biologi-
cal systems are adenosine, guanosine, cytidine, and uri-
dine (which contain ribose), and deoxyadenosine,
deoxyguanosine, deoxycytidine, and thymidine (which
contain deoxyribose).
See alsoNUCLEOTIDES.250 nucleosides
The nucleus is the central cell structure that houses the chromosomes.(Courtesy Darryl Leja, NHGRI, National Institutes of Health)